ACME - Model VOC-2 - Volatile Organic Compounds Detector
The VOC-2 detector is designed for enclosed spaces where chemical reagents or known VOC pollutants could leak into the air and pose a danger to personnel. This detector can cover up to 10,000 sq. ft. of clear, open space. It is designed to operate two-speed fans using two dry contacts that close at the appropriate low and high concentration levels for the toxic gas being detected. Standard calibration is with Toluene for set points at 1000 and 2000 PPM. Specific set-points for a wide variety of gases can be set at the factory. It also includes visual indicators on the front of the unit for low and high level with an audible alarm at the high level. The VOC-2 is constructed of heavy, damage-resistant PVC with vandal-proof screws. Units are available with integral (standard) or remote (optional) sensor heads. Typical installations include chemical storage facilities and personnel lounges in industrial buildings.
Indoor air quality problems, known as 'Sick Building Syndrome' have become issues of health and comfort in new and recently remodeled buildings. Buildings are called 'Sick' when their occupants experience symptoms such as headaches; eye, nose and throat irritation; dizziness; nausea; sensitivity to odors; and difficulty in concentrating.
Frequently encountered IAQ problems are caused by elevated indoor pollutants such as VOCs (Volatile Organic Compounds) and ineffective ventilation systems in buildings.
VOC emanations (such as toluene), are released by synthetic materials, cleaners, printers, paints, etc.
Once the VOC-2 detects concentrations in excess of calibrated levels, it demands ventilation and/or signals an audible alarm. The VOC-2 can be installed in stagnant areas of buildings where pollutant concentrations will rise. Standard units are calibrated using toluene. Units can also be calibrated with other compounds specified by the customer.
- Fully electronic system with solid state circuitry and built-in sensor.
- Compactcorrosion resistant gasketed enclosure.
- Two factory calibrated operating levels (Low & High) with visual indicators.
- Suitable for ventilation control.
- Audible alarm.
- High sensitivity and stability.
- Temperature compensated. High long-term reliability. Can be mounted on a wall or on a column.
- Gases detected: Toluene, hexane, benzene, xylene
- Sensor: N-type Metal Oxide Semiconductor (MOS)
- Mounting: Wall or column with brackets (supplied)
- Unit dimensions: 152mmH x 152mmW x 101mmD (6”H x 6”W x 4”D)
- Supply voltage: 120V AC (Also available 24 or 220V AC) 50-60 Hz, 20VA
- Ambient Temp.: 10-40º C (50-100º F)
- Dry control contacts: 2
- Contact rating: 5A @ 120V AC 1PH
- Contact relay 1: Low Level
- Contact relay 2: High Level
- LED indicators: Power On, Low Level, High Level
- Options: Pneumatic sampling : Cat. No.: VOC-2-EN
Principle of operation
The ACME VOC-2 uses a tin dioxide (SNO2) semiconductor gas sensor designed to detect volatile organic compounds. The decrease of electrical resistance of the sensor as it gets exposed to gases or vapors is used as an electrical output signal for detection.
There are two operating levels in the VOC- 2. At the LOW level the unit will activate a SPDT relay contact. At the HIGH level it will activate another SPDT relay contact and also will bring on an audible alarm. A thermistor is placed in the detection circuit in order to compensate for temperature variations. Built-in time delays on both ON or OFF relay operations avoid nuisance start-stops of fans or alarms. Units require 120V AC power. Because of possibly long storage time before it is initially energized, allow one week for unit to reach optimum operating conditions. If the unit was deenergized for a couple of days, the time required to have the unit back to normal operation is only a few minutes.
Supply, install and connect at locations shown on drawings Acme Volatile Organic Compounds Detection And Control Unit model VOC-2. Units shall be fully electronic incorporating solid state circuitry with built-in temperature compensation, factory calibrated at LOW and HIGH levels. Provide SPDT control relay contacts for each level. Each unit shall include visual indicators for power “ON” and operating status. HIGH level shall activate an integral audible alarm. Unit enclosure shall be gasketed, made of corrosion resistant material. Power supply shall be 120V AC unless specified.